A bicone is generally an antenna having two conical conductors, where the conical elements share a common axis, and a common vertex. The conical conductors extend in opposite directions. That is, the two flat portions of the cones face outward from one another. The flat portion of the cone can also be thought of as the base of the cone or the opening of the cone. The flat portion, or opening, of a cone is at the opposite end of the cone from the vertex or point of the cone. Bicone antennas are also called biconical antennas. Generally, a bicone antenna is fed from the common vertex. That is, the driving signal is applied to the antenna by a feed line connected at the antenna's central vertex area.
Positioning two cones so that the points (or vertices) of the two cones meet and the openings (or bases) of the two cones extend outward (opposite one another) results in a bowtie-like appearance. As such, some bicone antennas are called bowtie antennas.
Bicone antennas are generally omni-directional and thus may have low gain. The elevation pattern of a bicone can be directed or shaped using a lens. Such a lens is generally an additional external element that must be positioned within the field of the antenna in order to influence the radiation patterns of the bicone. These external elements may involve additional handling, manufacturing, cost, and complication. They may also reduce mechanical robustness of an antenna assembly. Furthermore, external lens elements may not be available for all bicone systems and may not fulfill specific elevation shaping requirements.
Accordingly, there is a need in the art for a broadband omni-directional bicone antenna with an integrated beam shaping lens where the bicone structure and lens can be machined or molded from a single piece of material.